There is a brand new web-site called Visual Dictionary. These ambitious folks are trying to get a photo of every single word they can. They have only been running for about a month, so they don't have a ton of words documented yet. They are looking for submissions. I think this would be really fun to work on. It's a different concept than the Visual Thesaurus. I dig the visual thesaurus, but wish it didn't cost to use. Probably the most ambitious of them all is the Flaming Fire Illustrated Bible. They are trying to get a illustration for every verse in the Bible.